3 ms·

> 43 million km away er, 149 million km away [0] not 43 [0] https://en.wikipedia.org/wiki/Sun https://en.wikipedia.org/wiki/Sun

grues-dinner 2y ago
The Solar Orbiter is 43 million km away from the Sun at its closest. If we got 17.5ish kW per square metre here on Earth, you'd know about it (but only briefly).
- KineticLensman 2y ago
  Oops, my bad
- PittleyDunkin 2y ago
  Hm, the article seems to have gotten its units wrong. Normally I'd trust the article but 43 million kilometers seems to match best with its orbit I can find documentation for.
  - KineticLensman 2y ago
    I was wrong with my initial jumping to conclusions, but on inspection I see that the underlying ESA press release [0] actually says "The images were taken when Solar Orbiter was less than 74 million kilometres from the Sun". Now I'm really confused. [0] https://www.esa.int/Science_Exploration/Space_Science/Solar_Orbiter/New_full_Sun_views_show_sunspots_fields_and_restless_plasma https://www.esa.int/Science_Exploration/Space_Science/Solar_...
    - lovecg 2y ago
      Well, they’re _technically_ correct.
    - grues-dinner 2y ago
      Presumably the images were taken on the way to perihelion. The orbit isn't circular, it's both highly eccentric and inclined relative to the ecliptic to get a view of the solar poles. A plane change is really hard on delta-v, so they tilt the orbit up bit by bit with repeated Venusian gravity assists. In the main science phase of the mission there are 14 planned perihelion approaches. There's a diagram here, but at least some of the information there seems preliminary as they eventually launched with a black "Solar Black" heat shield coating rather than white titanium dioxide because the latter wasn't sufficiently UV-stable. https://www.eoportal.org/satellite-missions/solar-orbiter-mission#solar-orbiter-mission https://www.eoportal.org/satellite-missions/solar-orbiter-mi...
dredmorbius 2y ago
grues-dinner was referring to the Solar Orbiter's distance from the Sun, and the intensity of radiation on the Orbiter. Not the Sun's distance from Earth, and radiant intensity at the Sun's surface. (The comment was unclearly worded and it took me a couple of readings and review of comments to realise the intent.)

grues-dinner 2y ago

The Solar Orbiter is 43 million km away from the Sun at its closest. If we got 17.5ish kW per square metre here on Earth, you'd know about it (but only briefly).

KineticLensman 2y ago
Oops, my bad
PittleyDunkin 2y ago
Hm, the article seems to have gotten its units wrong. Normally I'd trust the article but 43 million kilometers seems to match best with its orbit I can find documentation for.
- KineticLensman 2y ago
  I was wrong with my initial jumping to conclusions, but on inspection I see that the underlying ESA press release [0] actually says "The images were taken when Solar Orbiter was less than 74 million kilometres from the Sun". Now I'm really confused. [0] https://www.esa.int/Science_Exploration/Space_Science/Solar_Orbiter/New_full_Sun_views_show_sunspots_fields_and_restless_plasma https://www.esa.int/Science_Exploration/Space_Science/Solar_...
  - lovecg 2y ago
    Well, they’re _technically_ correct.
  - grues-dinner 2y ago
    Presumably the images were taken on the way to perihelion. The orbit isn't circular, it's both highly eccentric and inclined relative to the ecliptic to get a view of the solar poles. A plane change is really hard on delta-v, so they tilt the orbit up bit by bit with repeated Venusian gravity assists. In the main science phase of the mission there are 14 planned perihelion approaches. There's a diagram here, but at least some of the information there seems preliminary as they eventually launched with a black "Solar Black" heat shield coating rather than white titanium dioxide because the latter wasn't sufficiently UV-stable. https://www.eoportal.org/satellite-missions/solar-orbiter-mission#solar-orbiter-mission https://www.eoportal.org/satellite-missions/solar-orbiter-mi...

dredmorbius 2y ago

grues-dinner was referring to the Solar Orbiter's distance from the Sun, and the intensity of radiation on the Orbiter. Not the Sun's distance from Earth, and radiant intensity at the Sun's surface. (The comment was unclearly worded and it took me a couple of readings and review of comments to realise the intent.)